Question

an ideal refrigeration cycle is operating between 120 kPa and 1200 kPa. if R134a is the refrigerant, what is the compression work?

Answer 1

Pressure

$P_1=120kpa\\p_2=1200kpa$

$h_1=281KJ/kg\\h_2=234KJ/kg$

We know that

$\dot{w}=\dot{m}(h_2-h_1)$

${w}={m}(h_2-h_1)$

m=1kg

$$w=1\times(234-281)=47KJ/kg$$

$w=47kJ/kg$